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      1 /***************************************************************************/
      2 /*                                                                         */
      3 /*  ftgzip.c                                                               */
      4 /*                                                                         */
      5 /*    FreeType support for .gz compressed files.                           */
      6 /*                                                                         */
      7 /*  This optional component relies on zlib.  It should mainly be used to   */
      8 /*  parse compressed PCF fonts, as found with many X11 server              */
      9 /*  distributions.                                                         */
     10 /*                                                                         */
     11 /*  Copyright 2002-2015 by                                                 */
     12 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
     13 /*                                                                         */
     14 /*  This file is part of the FreeType project, and may only be used,       */
     15 /*  modified, and distributed under the terms of the FreeType project      */
     16 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
     17 /*  this file you indicate that you have read the license and              */
     18 /*  understand and accept it fully.                                        */
     19 /*                                                                         */
     20 /***************************************************************************/
     21 
     22 
     23 #include <ft2build.h>
     24 #include FT_INTERNAL_MEMORY_H
     25 #include FT_INTERNAL_STREAM_H
     26 #include FT_INTERNAL_DEBUG_H
     27 #include FT_GZIP_H
     28 #include FT_CONFIG_STANDARD_LIBRARY_H
     29 
     30 
     31 #include FT_MODULE_ERRORS_H
     32 
     33 #undef __FTERRORS_H__
     34 
     35 #undef  FT_ERR_PREFIX
     36 #define FT_ERR_PREFIX  Gzip_Err_
     37 #define FT_ERR_BASE    FT_Mod_Err_Gzip
     38 
     39 #include FT_ERRORS_H
     40 
     41 
     42 #ifdef FT_CONFIG_OPTION_USE_ZLIB
     43 
     44 #ifdef FT_CONFIG_OPTION_PIC
     45 #error "gzip code does not support PIC yet"
     46 #endif
     47 
     48 #ifdef FT_CONFIG_OPTION_SYSTEM_ZLIB
     49 
     50 #include <zlib.h>
     51 
     52 #else /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
     53 
     54  /* In this case, we include our own modified sources of the ZLib    */
     55  /* within the "ftgzip" component.  The modifications were necessary */
     56  /* to #include all files without conflicts, as well as preventing   */
     57  /* the definition of "extern" functions that may cause linking      */
     58  /* conflicts when a program is linked with both FreeType and the    */
     59  /* original ZLib.                                                   */
     60 
     61 #ifndef USE_ZLIB_ZCALLOC
     62 #define MY_ZCALLOC /* prevent all zcalloc() & zfree() in zutils.c */
     63 #endif
     64 
     65 #include "zlib.h"
     66 
     67 #undef  SLOW
     68 #define SLOW  1  /* we can't use asm-optimized sources here! */
     69 
     70 #if defined( _MSC_VER )      /* Visual C++ (and Intel C++)   */
     71   /* We disable the warning `conversion from XXX to YYY,     */
     72   /* possible loss of data' in order to compile cleanly with */
     73   /* the maximum level of warnings: zlib is non-FreeType     */
     74   /* code.                                                   */
     75 #pragma warning( push )
     76 #pragma warning( disable : 4244 )
     77 #endif /* _MSC_VER */
     78 
     79   /* Urgh.  `inflate_mask' must not be declared twice -- C++ doesn't like
     80      this.  We temporarily disable it and load all necessary header files. */
     81 #define NO_INFLATE_MASK
     82 #include "zutil.h"
     83 #include "inftrees.h"
     84 #include "infblock.h"
     85 #include "infcodes.h"
     86 #include "infutil.h"
     87 #undef  NO_INFLATE_MASK
     88 
     89   /* infutil.c must be included before infcodes.c */
     90 #include "zutil.c"
     91 #include "inftrees.c"
     92 #include "infutil.c"
     93 #include "infcodes.c"
     94 #include "infblock.c"
     95 #include "inflate.c"
     96 #include "adler32.c"
     97 
     98 #if defined( _MSC_VER )
     99 #pragma warning( pop )
    100 #endif
    101 
    102 #endif /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
    103 
    104 
    105 /***************************************************************************/
    106 /***************************************************************************/
    107 /*****                                                                 *****/
    108 /*****            Z L I B   M E M O R Y   M A N A G E M E N T          *****/
    109 /*****                                                                 *****/
    110 /***************************************************************************/
    111 /***************************************************************************/
    112 
    113   /* it is better to use FreeType memory routines instead of raw
    114      'malloc/free' */
    115 
    116   static voidpf
    117   ft_gzip_alloc( FT_Memory  memory,
    118                  uInt       items,
    119                  uInt       size )
    120   {
    121     FT_ULong    sz = (FT_ULong)size * items;
    122     FT_Error    error;
    123     FT_Pointer  p  = NULL;
    124 
    125 
    126     (void)FT_ALLOC( p, sz );
    127     return p;
    128   }
    129 
    130 
    131   static void
    132   ft_gzip_free( FT_Memory  memory,
    133                 voidpf     address )
    134   {
    135     FT_MEM_FREE( address );
    136   }
    137 
    138 
    139 #if !defined( FT_CONFIG_OPTION_SYSTEM_ZLIB ) && !defined( USE_ZLIB_ZCALLOC )
    140 
    141   local voidpf
    142   zcalloc ( voidpf    opaque,
    143             unsigned  items,
    144             unsigned  size )
    145   {
    146     return ft_gzip_alloc( (FT_Memory)opaque, items, size );
    147   }
    148 
    149   local void
    150   zcfree( voidpf  opaque,
    151           voidpf  ptr )
    152   {
    153     ft_gzip_free( (FT_Memory)opaque, ptr );
    154   }
    155 
    156 #endif /* !SYSTEM_ZLIB && !USE_ZLIB_ZCALLOC */
    157 
    158 
    159 /***************************************************************************/
    160 /***************************************************************************/
    161 /*****                                                                 *****/
    162 /*****               Z L I B   F I L E   D E S C R I P T O R           *****/
    163 /*****                                                                 *****/
    164 /***************************************************************************/
    165 /***************************************************************************/
    166 
    167 #define FT_GZIP_BUFFER_SIZE  4096
    168 
    169   typedef struct  FT_GZipFileRec_
    170   {
    171     FT_Stream  source;         /* parent/source stream        */
    172     FT_Stream  stream;         /* embedding stream            */
    173     FT_Memory  memory;         /* memory allocator            */
    174     z_stream   zstream;        /* zlib input stream           */
    175 
    176     FT_ULong   start;          /* starting position, after .gz header */
    177     FT_Byte    input[FT_GZIP_BUFFER_SIZE];   /* input read buffer  */
    178 
    179     FT_Byte    buffer[FT_GZIP_BUFFER_SIZE];  /* output buffer      */
    180     FT_ULong   pos;                          /* position in output */
    181     FT_Byte*   cursor;
    182     FT_Byte*   limit;
    183 
    184   } FT_GZipFileRec, *FT_GZipFile;
    185 
    186 
    187   /* gzip flag byte */
    188 #define FT_GZIP_ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
    189 #define FT_GZIP_HEAD_CRC     0x02 /* bit 1 set: header CRC present */
    190 #define FT_GZIP_EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
    191 #define FT_GZIP_ORIG_NAME    0x08 /* bit 3 set: original file name present */
    192 #define FT_GZIP_COMMENT      0x10 /* bit 4 set: file comment present */
    193 #define FT_GZIP_RESERVED     0xE0 /* bits 5..7: reserved */
    194 
    195 
    196   /* check and skip .gz header - we don't support `transparent' compression */
    197   static FT_Error
    198   ft_gzip_check_header( FT_Stream  stream )
    199   {
    200     FT_Error  error;
    201     FT_Byte   head[4];
    202 
    203 
    204     if ( FT_STREAM_SEEK( 0 )       ||
    205          FT_STREAM_READ( head, 4 ) )
    206       goto Exit;
    207 
    208     /* head[0] && head[1] are the magic numbers;    */
    209     /* head[2] is the method, and head[3] the flags */
    210     if ( head[0] != 0x1F              ||
    211          head[1] != 0x8B              ||
    212          head[2] != Z_DEFLATED        ||
    213         (head[3] & FT_GZIP_RESERVED)  )
    214     {
    215       error = FT_THROW( Invalid_File_Format );
    216       goto Exit;
    217     }
    218 
    219     /* skip time, xflags and os code */
    220     (void)FT_STREAM_SKIP( 6 );
    221 
    222     /* skip the extra field */
    223     if ( head[3] & FT_GZIP_EXTRA_FIELD )
    224     {
    225       FT_UInt  len;
    226 
    227 
    228       if ( FT_READ_USHORT_LE( len ) ||
    229            FT_STREAM_SKIP( len )    )
    230         goto Exit;
    231     }
    232 
    233     /* skip original file name */
    234     if ( head[3] & FT_GZIP_ORIG_NAME )
    235       for (;;)
    236       {
    237         FT_UInt  c;
    238 
    239 
    240         if ( FT_READ_BYTE( c ) )
    241           goto Exit;
    242 
    243         if ( c == 0 )
    244           break;
    245       }
    246 
    247     /* skip .gz comment */
    248     if ( head[3] & FT_GZIP_COMMENT )
    249       for (;;)
    250       {
    251         FT_UInt  c;
    252 
    253 
    254         if ( FT_READ_BYTE( c ) )
    255           goto Exit;
    256 
    257         if ( c == 0 )
    258           break;
    259       }
    260 
    261     /* skip CRC */
    262     if ( head[3] & FT_GZIP_HEAD_CRC )
    263       if ( FT_STREAM_SKIP( 2 ) )
    264         goto Exit;
    265 
    266   Exit:
    267     return error;
    268   }
    269 
    270 
    271   static FT_Error
    272   ft_gzip_file_init( FT_GZipFile  zip,
    273                      FT_Stream    stream,
    274                      FT_Stream    source )
    275   {
    276     z_stream*  zstream = &zip->zstream;
    277     FT_Error   error   = FT_Err_Ok;
    278 
    279 
    280     zip->stream = stream;
    281     zip->source = source;
    282     zip->memory = stream->memory;
    283 
    284     zip->limit  = zip->buffer + FT_GZIP_BUFFER_SIZE;
    285     zip->cursor = zip->limit;
    286     zip->pos    = 0;
    287 
    288     /* check and skip .gz header */
    289     {
    290       stream = source;
    291 
    292       error = ft_gzip_check_header( stream );
    293       if ( error )
    294         goto Exit;
    295 
    296       zip->start = FT_STREAM_POS();
    297     }
    298 
    299     /* initialize zlib -- there is no zlib header in the compressed stream */
    300     zstream->zalloc = (alloc_func)ft_gzip_alloc;
    301     zstream->zfree  = (free_func) ft_gzip_free;
    302     zstream->opaque = stream->memory;
    303 
    304     zstream->avail_in = 0;
    305     zstream->next_in  = zip->buffer;
    306 
    307     if ( inflateInit2( zstream, -MAX_WBITS ) != Z_OK ||
    308          zstream->next_in == NULL                     )
    309       error = FT_THROW( Invalid_File_Format );
    310 
    311   Exit:
    312     return error;
    313   }
    314 
    315 
    316   static void
    317   ft_gzip_file_done( FT_GZipFile  zip )
    318   {
    319     z_stream*  zstream = &zip->zstream;
    320 
    321 
    322     inflateEnd( zstream );
    323 
    324     /* clear the rest */
    325     zstream->zalloc    = NULL;
    326     zstream->zfree     = NULL;
    327     zstream->opaque    = NULL;
    328     zstream->next_in   = NULL;
    329     zstream->next_out  = NULL;
    330     zstream->avail_in  = 0;
    331     zstream->avail_out = 0;
    332 
    333     zip->memory = NULL;
    334     zip->source = NULL;
    335     zip->stream = NULL;
    336   }
    337 
    338 
    339   static FT_Error
    340   ft_gzip_file_reset( FT_GZipFile  zip )
    341   {
    342     FT_Stream  stream = zip->source;
    343     FT_Error   error;
    344 
    345 
    346     if ( !FT_STREAM_SEEK( zip->start ) )
    347     {
    348       z_stream*  zstream = &zip->zstream;
    349 
    350 
    351       inflateReset( zstream );
    352 
    353       zstream->avail_in  = 0;
    354       zstream->next_in   = zip->input;
    355       zstream->avail_out = 0;
    356       zstream->next_out  = zip->buffer;
    357 
    358       zip->limit  = zip->buffer + FT_GZIP_BUFFER_SIZE;
    359       zip->cursor = zip->limit;
    360       zip->pos    = 0;
    361     }
    362 
    363     return error;
    364   }
    365 
    366 
    367   static FT_Error
    368   ft_gzip_file_fill_input( FT_GZipFile  zip )
    369   {
    370     z_stream*  zstream = &zip->zstream;
    371     FT_Stream  stream  = zip->source;
    372     FT_ULong   size;
    373 
    374 
    375     if ( stream->read )
    376     {
    377       size = stream->read( stream, stream->pos, zip->input,
    378                            FT_GZIP_BUFFER_SIZE );
    379       if ( size == 0 )
    380         return FT_THROW( Invalid_Stream_Operation );
    381     }
    382     else
    383     {
    384       size = stream->size - stream->pos;
    385       if ( size > FT_GZIP_BUFFER_SIZE )
    386         size = FT_GZIP_BUFFER_SIZE;
    387 
    388       if ( size == 0 )
    389         return FT_THROW( Invalid_Stream_Operation );
    390 
    391       FT_MEM_COPY( zip->input, stream->base + stream->pos, size );
    392     }
    393     stream->pos += size;
    394 
    395     zstream->next_in  = zip->input;
    396     zstream->avail_in = size;
    397 
    398     return FT_Err_Ok;
    399   }
    400 
    401 
    402   static FT_Error
    403   ft_gzip_file_fill_output( FT_GZipFile  zip )
    404   {
    405     z_stream*  zstream = &zip->zstream;
    406     FT_Error   error   = FT_Err_Ok;
    407 
    408 
    409     zip->cursor        = zip->buffer;
    410     zstream->next_out  = zip->cursor;
    411     zstream->avail_out = FT_GZIP_BUFFER_SIZE;
    412 
    413     while ( zstream->avail_out > 0 )
    414     {
    415       int  err;
    416 
    417 
    418       if ( zstream->avail_in == 0 )
    419       {
    420         error = ft_gzip_file_fill_input( zip );
    421         if ( error )
    422           break;
    423       }
    424 
    425       err = inflate( zstream, Z_NO_FLUSH );
    426 
    427       if ( err == Z_STREAM_END )
    428       {
    429         zip->limit = zstream->next_out;
    430         if ( zip->limit == zip->cursor )
    431           error = FT_THROW( Invalid_Stream_Operation );
    432         break;
    433       }
    434       else if ( err != Z_OK )
    435       {
    436         error = FT_THROW( Invalid_Stream_Operation );
    437         break;
    438       }
    439     }
    440 
    441     return error;
    442   }
    443 
    444 
    445   /* fill output buffer; `count' must be <= FT_GZIP_BUFFER_SIZE */
    446   static FT_Error
    447   ft_gzip_file_skip_output( FT_GZipFile  zip,
    448                             FT_ULong     count )
    449   {
    450     FT_Error  error = FT_Err_Ok;
    451     FT_ULong  delta;
    452 
    453 
    454     for (;;)
    455     {
    456       delta = (FT_ULong)( zip->limit - zip->cursor );
    457       if ( delta >= count )
    458         delta = count;
    459 
    460       zip->cursor += delta;
    461       zip->pos    += delta;
    462 
    463       count -= delta;
    464       if ( count == 0 )
    465         break;
    466 
    467       error = ft_gzip_file_fill_output( zip );
    468       if ( error )
    469         break;
    470     }
    471 
    472     return error;
    473   }
    474 
    475 
    476   static FT_ULong
    477   ft_gzip_file_io( FT_GZipFile  zip,
    478                    FT_ULong     pos,
    479                    FT_Byte*     buffer,
    480                    FT_ULong     count )
    481   {
    482     FT_ULong  result = 0;
    483     FT_Error  error;
    484 
    485 
    486     /* Reset inflate stream if we're seeking backwards.        */
    487     /* Yes, that is not too efficient, but it saves memory :-) */
    488     if ( pos < zip->pos )
    489     {
    490       error = ft_gzip_file_reset( zip );
    491       if ( error )
    492         goto Exit;
    493     }
    494 
    495     /* skip unwanted bytes */
    496     if ( pos > zip->pos )
    497     {
    498       error = ft_gzip_file_skip_output( zip, (FT_ULong)( pos - zip->pos ) );
    499       if ( error )
    500         goto Exit;
    501     }
    502 
    503     if ( count == 0 )
    504       goto Exit;
    505 
    506     /* now read the data */
    507     for (;;)
    508     {
    509       FT_ULong  delta;
    510 
    511 
    512       delta = (FT_ULong)( zip->limit - zip->cursor );
    513       if ( delta >= count )
    514         delta = count;
    515 
    516       FT_MEM_COPY( buffer, zip->cursor, delta );
    517       buffer      += delta;
    518       result      += delta;
    519       zip->cursor += delta;
    520       zip->pos    += delta;
    521 
    522       count -= delta;
    523       if ( count == 0 )
    524         break;
    525 
    526       error = ft_gzip_file_fill_output( zip );
    527       if ( error )
    528         break;
    529     }
    530 
    531   Exit:
    532     return result;
    533   }
    534 
    535 
    536 /***************************************************************************/
    537 /***************************************************************************/
    538 /*****                                                                 *****/
    539 /*****               G Z   E M B E D D I N G   S T R E A M             *****/
    540 /*****                                                                 *****/
    541 /***************************************************************************/
    542 /***************************************************************************/
    543 
    544   static void
    545   ft_gzip_stream_close( FT_Stream  stream )
    546   {
    547     FT_GZipFile  zip    = (FT_GZipFile)stream->descriptor.pointer;
    548     FT_Memory    memory = stream->memory;
    549 
    550 
    551     if ( zip )
    552     {
    553       /* finalize gzip file descriptor */
    554       ft_gzip_file_done( zip );
    555 
    556       FT_FREE( zip );
    557 
    558       stream->descriptor.pointer = NULL;
    559     }
    560   }
    561 
    562 
    563   static FT_ULong
    564   ft_gzip_stream_io( FT_Stream  stream,
    565                      FT_ULong   pos,
    566                      FT_Byte*   buffer,
    567                      FT_ULong   count )
    568   {
    569     FT_GZipFile  zip = (FT_GZipFile)stream->descriptor.pointer;
    570 
    571 
    572     return ft_gzip_file_io( zip, pos, buffer, count );
    573   }
    574 
    575 
    576   static FT_ULong
    577   ft_gzip_get_uncompressed_size( FT_Stream  stream )
    578   {
    579     FT_Error  error;
    580     FT_ULong  old_pos;
    581     FT_ULong  result = 0;
    582 
    583 
    584     old_pos = stream->pos;
    585     if ( !FT_Stream_Seek( stream, stream->size - 4 ) )
    586     {
    587       result = FT_Stream_ReadULong( stream, &error );
    588       if ( error )
    589         result = 0;
    590 
    591       (void)FT_Stream_Seek( stream, old_pos );
    592     }
    593 
    594     return result;
    595   }
    596 
    597 
    598   /* documentation is in ftgzip.h */
    599 
    600   FT_EXPORT_DEF( FT_Error )
    601   FT_Stream_OpenGzip( FT_Stream  stream,
    602                       FT_Stream  source )
    603   {
    604     FT_Error     error;
    605     FT_Memory    memory;
    606     FT_GZipFile  zip = NULL;
    607 
    608 
    609     if ( !stream || !source )
    610     {
    611       error = FT_THROW( Invalid_Stream_Handle );
    612       goto Exit;
    613     }
    614 
    615     memory = source->memory;
    616 
    617     /*
    618      *  check the header right now; this prevents allocating un-necessary
    619      *  objects when we don't need them
    620      */
    621     error = ft_gzip_check_header( source );
    622     if ( error )
    623       goto Exit;
    624 
    625     FT_ZERO( stream );
    626     stream->memory = memory;
    627 
    628     if ( !FT_QNEW( zip ) )
    629     {
    630       error = ft_gzip_file_init( zip, stream, source );
    631       if ( error )
    632       {
    633         FT_FREE( zip );
    634         goto Exit;
    635       }
    636 
    637       stream->descriptor.pointer = zip;
    638     }
    639 
    640     /*
    641      *  We use the following trick to try to dramatically improve the
    642      *  performance while dealing with small files.  If the original stream
    643      *  size is less than a certain threshold, we try to load the whole font
    644      *  file into memory.  This saves us from using the 32KB buffer needed
    645      *  to inflate the file, plus the two 4KB intermediate input/output
    646      *  buffers used in the `FT_GZipFile' structure.
    647      */
    648     {
    649       FT_ULong  zip_size = ft_gzip_get_uncompressed_size( source );
    650 
    651 
    652       if ( zip_size != 0 && zip_size < 40 * 1024 )
    653       {
    654         FT_Byte*  zip_buff = NULL;
    655 
    656 
    657         if ( !FT_ALLOC( zip_buff, zip_size ) )
    658         {
    659           FT_ULong  count;
    660 
    661 
    662           count = ft_gzip_file_io( zip, 0, zip_buff, zip_size );
    663           if ( count == zip_size )
    664           {
    665             ft_gzip_file_done( zip );
    666             FT_FREE( zip );
    667 
    668             stream->descriptor.pointer = NULL;
    669 
    670             stream->size  = zip_size;
    671             stream->pos   = 0;
    672             stream->base  = zip_buff;
    673             stream->read  = NULL;
    674             stream->close = ft_gzip_stream_close;
    675 
    676             goto Exit;
    677           }
    678 
    679           ft_gzip_file_io( zip, 0, NULL, 0 );
    680           FT_FREE( zip_buff );
    681         }
    682         error = FT_Err_Ok;
    683       }
    684     }
    685 
    686     stream->size  = 0x7FFFFFFFL;  /* don't know the real size! */
    687     stream->pos   = 0;
    688     stream->base  = 0;
    689     stream->read  = ft_gzip_stream_io;
    690     stream->close = ft_gzip_stream_close;
    691 
    692   Exit:
    693     return error;
    694   }
    695 
    696 
    697   /* documentation is in ftgzip.h */
    698 
    699   FT_EXPORT_DEF( FT_Error )
    700   FT_Gzip_Uncompress( FT_Memory       memory,
    701                       FT_Byte*        output,
    702                       FT_ULong*       output_len,
    703                       const FT_Byte*  input,
    704                       FT_ULong        input_len )
    705   {
    706     z_stream  stream;
    707     int       err;
    708 
    709 
    710     /* check for `input' delayed to `inflate' */
    711 
    712     if ( !memory || ! output_len || !output )
    713       return FT_THROW( Invalid_Argument );
    714 
    715     /* this function is modeled after zlib's `uncompress' function */
    716 
    717     stream.next_in  = (Bytef*)input;
    718     stream.avail_in = (uInt)input_len;
    719 
    720     stream.next_out  = output;
    721     stream.avail_out = (uInt)*output_len;
    722 
    723     stream.zalloc = (alloc_func)ft_gzip_alloc;
    724     stream.zfree  = (free_func) ft_gzip_free;
    725     stream.opaque = memory;
    726 
    727     err = inflateInit2( &stream, MAX_WBITS );
    728     if ( err != Z_OK )
    729       return FT_THROW( Invalid_Argument );
    730 
    731     err = inflate( &stream, Z_FINISH );
    732     if ( err != Z_STREAM_END )
    733     {
    734       inflateEnd( &stream );
    735       if ( err == Z_OK )
    736         err = Z_BUF_ERROR;
    737     }
    738     else
    739     {
    740       *output_len = stream.total_out;
    741 
    742       err = inflateEnd( &stream );
    743     }
    744 
    745     if ( err == Z_MEM_ERROR )
    746       return FT_THROW( Out_Of_Memory );
    747 
    748     if ( err == Z_BUF_ERROR )
    749       return FT_THROW( Array_Too_Large );
    750 
    751     if ( err == Z_DATA_ERROR )
    752       return FT_THROW( Invalid_Table );
    753 
    754     return FT_Err_Ok;
    755   }
    756 
    757 
    758 #else /* !FT_CONFIG_OPTION_USE_ZLIB */
    759 
    760   FT_EXPORT_DEF( FT_Error )
    761   FT_Stream_OpenGzip( FT_Stream  stream,
    762                       FT_Stream  source )
    763   {
    764     FT_UNUSED( stream );
    765     FT_UNUSED( source );
    766 
    767     return FT_THROW( Unimplemented_Feature );
    768   }
    769 
    770 
    771   FT_EXPORT_DEF( FT_Error )
    772   FT_Gzip_Uncompress( FT_Memory       memory,
    773                       FT_Byte*        output,
    774                       FT_ULong*       output_len,
    775                       const FT_Byte*  input,
    776                       FT_ULong        input_len )
    777   {
    778     FT_UNUSED( memory );
    779     FT_UNUSED( output );
    780     FT_UNUSED( output_len );
    781     FT_UNUSED( input );
    782     FT_UNUSED( input_len );
    783 
    784     return FT_THROW( Unimplemented_Feature );
    785   }
    786 
    787 #endif /* !FT_CONFIG_OPTION_USE_ZLIB */
    788 
    789 
    790 /* END */
    791